Pretty much what I’ve been saying in the last few blog posts. The only other thing I proposed, is to actually use the money to store the carbon somewhere other than the atmosphere.

Hopefully they’ll come up with a map of different types of land (arable, forest, desert, etc.) as they further along their research.

Solving Global Warming… with Startups?

So, here’s one suggestion on how to solve global warming using existing tech. First, the facts: each ton of CO2 causes $21 of economic damage. This means that:

  • A tax of $0.21 per gallon on fossil-fuels will be enough to pay for the amount of CO2 produced. This would raise the price of e.g. gasoline by 6% (at $3.50/gallon).
  • A tax of $0.022 per kWh of coal-produced electricity will be enough to pay for the amount of CO2 produced. This would raise the price of coal-powered electricity by 22% (at $0.10/kWh).
  • By taxing the two items above, well over 90% of CO2 emissions are covered. The revenue from this tax could be applied to solve global warming.

From further research, I found the cost of one ton of CO2 emitted can be as high as $124, depending on estimates. Also, the social cost of coal is approximately $0.21/kWh. So with an average true cost of $0.31/kWh of coal-produced electricity (about half in US), how fast does solar pay for itself, I wonder? Probably less than two years in most places, but that’s another blog post…

From an entrepreneur’s point of view, however, the higher tax just sweetens the deal, assuming governments are willing to pay at least a part of that money to startups that sequester CO2.

So here are several proposed business models for just such a startup:

  • Buy non-arable land for really cheap, and hire people to convert that land to forests using permaculture techniques; something similar is done by a non-profit mentioned in the previous post. Part of the plant mass can be harvested for things like food and medicine; material for houses, furniture, clothes, and even plastic; and the forests can become tourism destinations, as well as other uses. By measuring the growth cycles of plants, one could maintain an optimum rate of sequestration by cutting down trees once their growth rate slows down and plant new trees in their stead.
  • Buy land as mentioned above, and use sustainable techniques to turn the barren land into savannas using cows.
  • Use decommissioned C-130 military planes to plant 0.9 million trees per day by dropping them as tree bombs. To plant all the trees needed, it would take 12,000 plane-years: 2500 planes tree-bombing for 5 years (the number of planes given in the article), or 12,000 planes bombing for the duration of one year.

In fact, one could combine all the above techniques: Use the planes as a first pass to plant trees in a certain patterns, then hire people to maintain the forest and herd cattle, thus turning non-arable land into a marble-cake of forests and savannas.

But, you might say, does it scale? What if we decided to sequester all our carbon that we as humans produce? There are a total of 33 billion non-arable acres in the world (excluding Antarctica) [1]. The current forest covers at least 8 billion acres. If we can grow forests on another 9 billion acres (or less than 1/3 of non-arable land), we can remove all the CO2 that is being produced.

So, we have the space, we have the means to get this done quickly, and we have the funds (as a tax on things that cause almost all of the CO2 emissions). What am I missing?

[1] I had a really hard time finding this number, so I eyeballed this map and took a conservative estimate of 35% arable land, or 65% non-arable land. The above number does not count Antarctica.

An armchair engineer’s plan to solve global warming

Recently, I needed something to distract me from work that needed to be done. So I calculated how many trees each person would need to plant to offset our carbon emissions. For the whole world, the average is ~200 trees. For the American, it comes out to ~1200 trees per person (per lifetime of the tree, which can be roughly compared to a human lifetime). Currently, one can have trees planted for a cost of ~$5/tree if ordering more than 100 trees. So for a lifetime cost of $6000, an American can have all of his or her carbon offset.

Now, I realize it’s more complicated than that. For one, where would you plant these trees? Then I realized it’s not a problem. You can selectively cut down existing trees and plant new ones in their stead. The cut down trees can be used for anything you want, as long as you don’t convert their carbon into CO2 by e.g. burning them: use them to make houses, furniture, etc; or even bury them to sequester carbon and gradually become soil within a decade or so (a practice known as hugelkultur).

So after writing this, I visited wikipedia’s entry on tree planting, and it turns out it’s even cheaper: “As little as US$90 will plant 900 trees, enough to annually remove as much carbon dioxide as is annually generated by the fossil-fuel usage of an average United States resident.” However, the trees should be planted in the tropics to mitigate climate change.

Now, which organisation will shut up and take my $360 to offset my family’s carbon emissions?

EDIT: This one will, for the same rate as mentioned above. Also, see more discussion at Hacker News.